Detailed explanation of KODO framework technical principles in the Java class library

The Kodo framework is a popular Java persistence solution to manage data interaction between applications and databases.It provides a powerful and flexible tool for simplifying database operations and improving the performance and scalability of applications. The technical principles of the Kodo framework are mainly based on the following core concepts: 1. Data persistence: Kodo converts Java objects into persistent data in the database by providing object-relationship mapping (ORM) technology.It provides two ways: annotation and XML configuration files to define the mapping relationship between the physical class and the database table. 2. Data access: Kodo provides a set of powerful APIs to perform data access operations, such as creating, updating, deleting and querying.It supports data query using JPQL (Java Persistence Query Language) or native SQL statements to meet different data retrieval needs. 3. Affairs management: Kodo framework supports transaction management to ensure data consistency and integrity in the database operation process.It provides two ways: declaration -type transactions and programming transactions, which can easily handle the submission, rollback and isolation level of transactions. 4. Cache management: The Kodo framework provides excellent performance and scalability through the built -in cache mechanism.It supports multi -level cache, including object cache and query cache to reduce frequent access to databases and improve the response speed of applications. 5. Delay loading: The KODO framework uses delay loading technology. Only when the database is needed when needed.This can reduce unnecessary data access and improve the performance and efficiency of applications. Below is an example code using the Kodo framework: import javax.persistence.*; @Entity @Table(name = "users") public class User { @Id @GeneratedValue(strategy = GenerationType.IDENTITY) private Long id; @Column(name = "username") private String username; @Column(name = "password") private String password; // Getters and setters } public class Main { public static void main(String[] args) { // Create Entity Manager Factory EntityManagerFactory emf = Persistence.createEntityManagerFactory("my-persistence-unit"); // Create Entity Manager EntityManager em = emf.createEntityManager(); // Create a user object User user = new User(); user.setUsername("admin"); user.setPassword("password"); // Open transaction em.getTransaction().begin(); // Save the user to the database em.persist(user); // Submit a transaction em.getTransaction().commit(); // Close Entity Manager and Entity Manager Factory em.close(); emf.close(); } } In the above code, we first use the@Entity` annotation to map the `user` class to the` users` table in the database.Then, in the `Main` method of the` main` class, we first created an `EntityManagerFactory` object to create an instance of` EntityManager`.Then, we create a new user object and save it into the database through the `Persist` method of` EntityManager`.Finally, we submit a transaction and close the `EntityManager` and` EntityManagerFactory`. According to specific needs, we also need to configure some related parameters of the KODO framework, such as database connection, cache configuration, and persistent unit.These configurations can be defined by a XML file called `Persistence.xml`, or configure it using an annotation method. In summary, the Kodo framework is a powerful and flexible Java persistence solution. Through its technical principles and related configurations, we can easily realize the data interaction between the Java application and the database, and improve the performance of the application and the performance and the performance of the application and the performance of the application and the performance of the application andScalability.